The goals of the current mixed methods study—the Illinois Principal Preparation Implementation Review Project (I-PREP)—are to describe how the new policy is being implemented, learning which aspects of the implementation have been challenging and why they present challenges, and how programs are addressing challenges and realizing improvements in the preparation of their candidates. This report presents findings from the first phase of the study. Results of interviews with program representatives and key Illinois education stakeholders showed the majority of those interviewed support the goals of the new policy and have a positive outlook on its future impact of principal preparation in Illinois. Although some concerns about the implementation were expressed, most believe the redesigned principal preparation programs will ultimately create better prepared school administrators, improved student achievement, and more successful schools. The final report, due in summer 2016, will integrate the findings from this interim report, site visits with selected programs, and a survey with all programs to provide research-based insights in how to improve the policy and its implementation.